Some natural bitumens and heavy crude oils, including those occurring in North West Canada, contain organic acids. For instance, Peace River bitumen contains naphthenic, sulphonic and other organic acids in such quantities that between 3 and 5 mg of potassium hydroxide are required to neutralize one g of bitumen (Total Acid Number, TAN).
Under normal operating conditions such bitumen causes no corrosion of any consequence in producing wells, production facilities and pipelines. However, in the refinery, at high process temperatures, very severe corrosion of carbon steel process equipment will occur.
One approach of preventing such corrosion is protecting all refinery process facilities exposed to acidic crude oil by the use of stainless steel. Another approach is to eliminate the acids up-stream, in the field production facilities. The latter approach is the subject of this invention.